methods: {
getHomeInfo() {
axios.get("/js/index.json").then(this.getHomeInfoSucc());
//err：undefined
axios.get("/js/index.json").then(function(res) {
console.log(res.data);
});
//Data available
},
getHomeInfoSucc(res) {
console.log(res);
}
}
I used Axios in Vue to use the anonymous function in Axios's then () to get data, but in then (), I call the function in methods to get the response data undefined
You need a callback:
methods: {
getHomeInfo() {
axios.get("/js/index.json").then((res) => this.getHomeInfoSucc(res));
//err：undefined
axios.get("/js/index.json").then(function(res) {
console.log(res.data);
});
//Data available
},
getHomeInfoSucc(res) {
console.log(res);
}
}
Related
this is my vue file which accepts the id from table. this works I can get the data id from the table row
showProd (id) {
Products.showProd().then((response) => {
console.log(show1prod.product_name)
})
.catch((error) => {
alert(error)
})
this is my config file for calling the axios.get I can reach the backend but not generating the query because this url/api sends an object I believe not the id number
export default {
async showProd(id) {
return Api.get('/products/{id}',id)
},
loadProds () {
return Api.get('/products')
}
}
First make sure your API call is correct:
export default {
showProd(id) { // async not needed, axios returns promise
return axios.get('/products/' + id)
},
loadProds () {
return axios.get('/products')
}
}
You can than call these functions:
showProd (id) {
Products.showProd(id).then((response) => { // Note the id in the call
console.log(response.data.product_name) // Use the response object
})
.catch((error) => {
alert(error)
})
This is my first class where I defined all db functions.
import React,{Component} from 'react';
var Datastore = require('react-native-local-mongodb')
, db = new Datastore({ filename: 'asyncStorageKey', autoload: true });
export default class RDDBManager {
static dbmanager = null;
static getInstance() {
if (RDDBManager.dbmanager == null) {
RDDBManager.dbmanager = new RDDBManager();
}
return this.dbmanager;
}
constructor () {
}
//insert items
insertItem(item){
var json = item.toJsonString();
console.log("Inside insertItem ::: "+json);
db.insert(json,function(err,newDos){
return newDos;
});
}
//read single item
readItem(itemId){
db.findOne({ id: itemId }, function (err, doc) {
return doc;
});
}
//read all items
readAllItems(){
db.find({}, function (err, docs) {
return docs;
});
}
getModalData(modalName) {
this.readAllItems();
}
//update
updateItem(itemId){
db.update({ id: itemId }, { $set: { system: 'solar system' } }, { multi: true }, function (err, numReplaced) {
});
}
//delete item
deleteItem(itemId){
db.remove({ id: itemId }, {}, function (err, numRemoved) {
return numRemoved;
});
}
}
But,when I try to call these functions from another class,the data is undefined.
loadDataFromDB() {
var items = RDDBManager.getInstance().readAllItems();
console.log("Items ======>>>>>> "+items);
}
the value of items is undefined.
This is because you are not doing things right, Your readallitems is async in nature so you have to do something like this:-
//read all items
readAllItems(callback){
db.find({}, function (err, docs) {
callback(docs);
});
}
And For calling something like this:-
loadDataFromDB() {
RDDBManager.getInstance().readAllItems(function(items){
console.log("Items ======>>>>>> "+items);
});
}
Alternatively, you can use promise or Async await also.
I am using Angular 5 and want to return data from function getDionaeaResults in json format after subscribing to service
getDionaeaResults(sql) : any {
this.dionaeaService.getDionaeaConnectionLogs(sql).subscribe(res => {
this.data = res;
}),
(error: any) => {
console.log(error);
});
return this.data;
}
After calling this function, this.totalAttacks prints undefined.
getTotalAttack() {
this.totalAttacks = this.getDionaeaResults("some query")
console.log(this.totalAttacks,'attacks')
}
Would suggest using the Obseravable .map() function.
getDionaeaResults(sql) : Observable<any> {
return this.dionaeaService
.getDionaeaConnectionLogs(sql)
.map(res => res);
}
getTotalAttack(sql){
this.getDionaeaResults("some query")
.subscribe(
res => { this.totalAttacks = res; },
err => { console.log(err); }
);
}
this.getDionaeaResults is returning undefined because the service you're calling is asynchronous you have to wait for the subscribe callback. as Observables are asynchronous calls
this.data=res
might execute after the return statement. You can perhaps call that dionaeaService directly inside getTotalAttack() function, like this:
getTotalAttack(sql){
this.dionaeaService.getDionaeaConnectionLogs(sql).subscribe(res => {
this.totalAttacks = res;
}),
(error: any) => {
console.log(error);
});
}
Let's say I have following action:
export function signIn(data) {
return {
type: USER_SIGN_IN,
promise: api.post('/sign_in', data)
}
}
and following middleware:
export default function promiseMiddleware() {
return next => action => {
const { promise, type, ...rest } = action
if (!promise) {
return next(action)
}
const SUCCESS = `${type}_SUCCESS`
const REQUEST = `${type}_REQUEST`
const ERROR = `${type}_ERROR`
next({ type: REQUEST, ...rest })
return promise
.then(res => {
next({ response: res.data, type: SUCCESS, ...rest })
return true
})
.catch(error => {
...
})
}
}
This code is loosely based on https://github.com/reactGo/reactGo/
But what if in then callback after calling next I want to make a redirect to another path?
I did following. I passed redirect url through action:
export function signIn(data) {
return {
type: USER_SIGN_IN,
promise: api.post('/sign_in', data),
redirect: '/'
}
}
and added another call of next method with push from react-router-redux.
import { push } from 'react-router-redux'
export default function promiseMiddleware() {
return next => action => {
const { promise, type, redirect, ...rest } = action
...
return promise
.then(res => {
next({ response: res.data, type: SUCCESS, ...rest })
next(push(redirect))
return true
})
.catch(error => {
...
})
}
}
It seems like it works, but I'm not sure if this is a good idea or if there are some pitfalls of multiple next calls and I shouldn't do like this?
Maybe there are some better approaches for implementing such redirects?
I'm building a REST API using node and restify that communicaties with an elasticsearch database. Now when I delete an object, I want this to do a kind of cascading delete to some other objects. I know this is not really what to use elasticsearch for but bear with me.
So here is my code:
function deleteHostname(req, res, next) {
res.setHeader('Access-Control-Allow-Origin', '*');
var endpoints = [];
client.search({
index: 'test',
type: 'something',
body: {
from: 0, size: 100,
query: {
match: {
hostname: 'www.test.com'
}
}
}
}).then(function (error, resp) {
if(error) {
res.send(error);
}
endpoints = resp.hits.hits;
for (index = 0, len = endpoints.length; index < len; ++index) {
client.delete({
index: 'test',
type: 'something',
id: endpoints[index]._id
}, function (error, response) {
if(error) {
res.send(error);
}
});
}
res.send(endpoints);
return next();
});
}
So basically I just want to search for any objects with hostname www.test.com ( I just hard coded this to test it ). Then I want to delete all objects I found. It follows the error path and sends me this:
{
"took":1,
"timed_out":false,
"_shards":{
"total":5,
"successful":5,
"failed":0
},
"hits":{
"total":1,
"max_score":2.098612,
"hits":[
{
"_index":"test",
"_type":"something",
"_id":"123456",
"_score":2.098612,
"_source":{
"duration":107182,
"date":"2016-05-04 00:54:43",
"isExceptional":true,
"hostname":"www.test.com",
"eta":613,
"hasWarnings":false,
"grade":"A+",
"ipAddress":"ipip",
"progress":100,
"delegation":2,
"statusMessage":"Ready"
}
}
]
}
}
So in my opinion this doesn't look like an error? So why am I getting it back as an error? If I remove:
if(error) {
res.send(error);
}
From my code, I won't get any response.
You need to change your code like this (see the changes denoted by -> to the left):
if(error) {
1-> return res.send(error);
}
endpoints = resp.hits.hits;
for (index = 0, len = endpoints.length; index < len; ++index) {
2-> (function(id){
client.delete({
index: 'test',
type: 'something',
3-> id: id
}, function (error, response) {
if(error) {
4-> next(error);
}
});
5-> })(endpoints[index._id]);
}
6-> //res.send(endpoints);
I'm now explaining each change:
If you don't return you'll send the error and then you'll continue with processing the hits
(3/5) Since client.delete is an asynchronous function, you need to call it in an anonymous function
In case of error you need to call next(error) not res.send
You cannot send the response at this point since your for loop might not be terminated yet. Instead of a for loop, you should use the excellent async library instead (see an example of using asynch.each below)
Async example:
var async = require('async');
...
if(error) {
return res.send(error);
}
endpoints = resp.hits.hits;
async.each(endpoints,
function(endpoint, callback) {
client.delete({
index: 'test',
type: 'something',
id: endpoint._id
}, callback);
},
// this is called when all deletes are done
function(err){
if (err) {
next(err);
} else {
res.send(endpoints);
next();
}
}
);
Another solution for you to achieve exactly what you want is to use the delete by query plugin. That feature allows you to do all the above in a single query.
If you are still on ES 1.x, delete-by-query is still part of the core and you can simply call the deleteByQuery function of the Javascript client.
If you are on ES 2.x, delete-by-query is now a plugin, so yo need to install it and then also require the deleteByQuery extension library for the Javascript client
function deleteHostname(req, res, next) {
res.setHeader('Access-Control-Allow-Origin', '*');
client.deleteByQuery({
index: 'test',
type: 'something',
body: {
query: {
match: { hostname: 'www.test.com' }
}
}
}, function (error, response) {
if (error) {
next(error);
} else {
res.send(endpoints);
next();
}
});
}